This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX175S, with the same bore, stroke, output force, port and mounting, so it fits the same application. The SAI replacement keeps the same ISO 15552 mounting interface, bore, stroke, output force and accessories, so it drops straight into existing fixtures. It is the current-production version of this cylinder with an upgraded piston seal.
Airtac SI125 Standard Cylinder SI125BX175S
The AirTAC SI125 Standard Cylinder SI125BX175S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 175mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX175S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke175 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX175S
- No minimum order. A single piece can be ordered.
- Ready in 3–5 business days. That is the time we take to process the order and hand it to the carrier. Transit time after that depends on the destination.
About the Airtac SI125 Standard Cylinder SI125BX175S
The AirTAC SI125BX175S is a discontinued double-acting ISO 15552 profile cylinder featuring a 125 mm bore, 175 mm stroke, and a SUS304 stainless steel rod. Delivering 6136 N push force at 0.5 MPa, it is replaced by the direct replacement SAI125BX175S. This upgrade shares the exact ISO 15552 mounting interface, G1/2 port, and M27x2 thread, fitting existing fixtures perfectly.
The SAI replacement introduces an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The SAI family also adds SAIL and BSAI lock variants absent from the SI line, while the original -S magnet supports legacy CS1-B/DS1-B sensors.
Airtac SI125 Standard Cylinder SI125BX175S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX175S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX175S |
| Bore size | Ø125 mm |
| Stroke | 175 mm |
| Acting type | Double acting |
| Port size | G1/2 |
| Rod thread | M27×2.0 |
| Fluid | Air (filtered by 40µm element) |
|---|---|
| Operating pressure | 0.15 – 1.0 MPa |
| Proof pressure | 1.5 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 30 – 500 mm/s |
| Cushion | Adjustable, 40 mm |
| Max standard stroke | Up to 1500 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI125BX175S carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø125mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 6136 N | 5734 N |
| 0.7 MPa | 8590 N | — |
| Max (@1.0 MPa) | 1251 kgf | |
The SAI125BX175S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI125 Standard Cylinder SI125BX175S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×175 | Stroke length in mm. |
| -S | Optional built-in magnet for sensor position sensing. |
Legacy SI-family variants: SID (double rod), SIJ (adjustable stroke) — each maps to its SAI equivalent (SID→SAID, SIJ→SAIJ). Rod material: carbon steel (blank) / SUS420J2 (A) / SUS304 (B).
Where the Airtac SI125 Standard Cylinder SI125BX175S Is Used
Heavy Press Clamping
Applies the 6136 N push force at 0.5 MPa to secure heavy fabrication components during machining or welding operations.
Stainless Rod Actuation
Leverages the SUS304 rod for corrosion resistance in washdown environments while shifting heavy mechanical assemblies.
Replacing the Airtac SI125 Standard Cylinder SI125BX175S with the SAI125BX175S
To replace the SI125BX175S, order the SAI125BX175S, verifying the ISO 15552 interface, 175 mm stroke, G1/2 port, and mounting accessory. The -B rod is SUS304 stainless steel, and the -S magnet works with legacy CS1-B/DS1-B switches (the SAI uses current AirTAC switches). Sizing both ways: a 100 mm bore yields 3927 N push at 0.5 MPa, while a 160 mm bore yields 10053 N. Note that a plain cylinder drifts on air loss as the cushion only decelerates; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. For this 175 mm stroke, ensure guide alignment to prevent rod bending under side loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX175S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI125 Standard Cylinder SI125BX175S FAQ
Yes, the SI125BX175S is discontinued. The direct replacement is the SAI125BX175S, which shares the same ISO 15552 mounting interface, 125 mm bore, 175 mm stroke, output force, G1/2 port, and SUS304 rod.
The 125 mm bore provides 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push at 0.7 MPa, 11045 N push at 0.9 MPa, and a theoretical max of 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX175S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX175S replacement — usually within 7-8 hours.